2026 Southeastern Residency Conference

TITLE: Incidence of Mechanical Ventilation in the Emergency Department among Patients with Acute Pulmonary Edema Utilizing High versus Low Dose Intravenous Nitroglycerin

AUTHORS: Saralyn Hardin, Kira Council, Erica Merritt, Megan Cavagnini

BACKGROUND: Heart failure affects approximately 2% of adults in the United States, with an estimated 33% at risk of developing the condition. It is classified into progressive stages, with Stage C characterized by symptomatic disease and Stage D representing advanced heart failure. Patients with Stage D heart failure frequently experience debilitating symptoms that significantly impact daily life and often result in recurrent hospitalizations. According to the American Heart Association/American College of Cardiology/Heart Failure Society of America guidelines, nitroglycerin may be considered for the management of pulmonary edema in acute heart failure presentations, provided hypotension is not present. Nitroglycerin is a targeted vasodilator that primarily reduces preload; at higher doses, it also induces arterial vasodilation, thereby decreasing afterload. While typically initiated at low infusion rates, higher rates (≥100 mcg/min) have demonstrated improved clinical outcomes in the treatment of pulmonary edema.

METHODS: This retrospective, observational chart review evaluated the incidence of mechanical ventilation in patients in the emergency department at St. Joseph’s or Candler Hospitals diagnosed with acute pulmonary edema based on the nitroglycerin dose in the first hour of treatment.  The health system’s software and a computer-generated list using MedMined services was used to identify patients with acute pulmonary edema then filtered based on the inclusion and exclusion criteria between January l, 2023, and January 1, 2024.
Patients were identified, and data was gathered to include demographic information, nitroglycerin infusion rate within the first hour, blood pressure, baseline serum creatinine and admission location. The primary objective was to determine the rate of mechanical ventilation in patients who received high dose nitroglycerin in comparison to those who received low dose nitroglycerin. The secondary endpoints of the study were the average nitroglycerin dose within the first hour of initiation, admitted level of care, percent of patients that develop acute kidney injury or hypotension after infusion initiation, average length of time in minutes the infusion was active, and all-cause mortality.

RESULTS: Three patients were screened for eligibility with 36 meeting inclusion criteria. Ten (27%) received high dose nitroglycerin (rate ≥100mcg/min) and 26 (72%) received low dose nitroglycerin (rate <100mcg/min). The mean number of patients requiring mechanical intubation was found to be 0.2 in the high dose nitroglycerin compared to 0.04 in the low dose group. Of the thirty-six patients three required mechanical ventilation and one of the three had a prior medical history revealing asthma and chronic obstructive pulmonary disease. Overall, there was found to be no statically significant correlations between the nitroglycerin dosing group and adverse events including admittance into the intensive care unit, incidence of hypotension, incidence of acute kidney injury, and all-cause mortality.

CONCLUSION: The overall nitroglycerin dosage administered to patients during the first hour following a pulmonary edema diagnosis was not comparable to the incidence of mechanical intubation in prior studies. Considering the study’s limitations of small sample size, further research with larger, multicenter data should explore potential relationship between nitroglycerin dosing within the first hour of diagnosis to adverse events.